JP2015108628A - Method of measuring diameter of cylinder liner of two-stroke crosshead internal combustion engine, diameter measuring device, and flexible ring used for the method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of measuring a diameter of a cylinder liner while a two-stroke crosshead engine is in a temporarily non-operation state, and to provide a diameter measuring device used by the method.SOLUTION: An electronic diameter measuring device 10 for measuring a diameter of a cylinder liner 106 is inserted in the inside of the cylinder liner 106 of an internal combustion engine through a scavenging port 103 to be arranged at a measurement position and measures an inside diameter of the cylinder liner 106 as electronic parameters.

Description

  The present invention relates to a method for measuring the diameter (cylinder liner diameter) of a cylinder liner of a two-stroke crosshead internal combustion engine (crosshead type two-stroke internal combustion engine), and the diameter measuring device ( The present invention relates to a method for measuring an inner diameter of a cylinder liner by inserting a diameter gauge device) into a cylinder liner through a scavenging port of the cylinder liner and disposing it at a measurement position.

Background of the Invention and Summary of the Invention

  In large two-stroke crosshead internal combustion engines, it is important to keep a record of cylinder wear. While the engine is operating, the pressure in the combustion chamber presses the piston ring radially outward against the inner surface of the cylinder liner, so that the load on the cylinder liner of the piston ring causes cylinder wear. In engine maintenance, it is important to obtain cylinder wear information over time, and in order to establish that record, measurements of the actual wear condition of the engine's individual cylinder liners are performed periodically. . Cylinder wear is typically measured when the engine is stopped for overhaul or to repair other parts of the engine. However, engine conditions change over time during maintenance.

  Large two-stroke internal combustion engines are typically used as the main engine of ships, but for many types of ships, the time to dock at the port is short, and for container ships, it is typically about 5 hours. Such a short time is insufficient to measure the cylinder liner wear of the cylinder in the engine.

  The measuring device disclosed in U.S. Pat. No. 3,090,125 comprises an elongate base member and an adjustable rod that is pivotally attached thereto and can be partially inserted from the scavenging port of the cylinder liner. The apparatus comprises mechanical adjustment means for shortening and extending the length of the rod and other mechanical means operable to swing the rod relative to the base member. ing. This measuring device is configured to be partially inserted into the cylinder liner via the scavenging port and to be operated from the outside. When the measurement is complete, the device is removed.

  A commonly used method for measuring cylinder liner wear in a two-stroke crosshead engine is to disassemble the cylinder liner cover or exhaust valve housing to ensure a sufficient size passage at the top of the cylinder liner. The diameter measuring device is lowered inside the cylinder and diameter measurement is performed at various height positions in the cylinder liner.

  The diameter measuring device disclosed in Danish Patent No. 152628 is configured to measure the inner diameter of the cylinder liner after the cylinder cover is disassembled and removed. The diameter measuring device includes a frame portion having two support legs at one end thereof, and a measurement probe disposed on the opposite side in the diametrical direction with respect to the two support legs. The frame portion is provided with a handle disposed near the end of the support leg and a dial gauge mechanically connected to the measurement probe. When this diameter gauge device is lowered into the cylinder liner by a handle or a bond, the support leg and the measurement probe come into contact with the cylinder liner and serve as a reference point for measurement, and the measured value is indicated on the dial gauge. And visually read by the operator handling the diameter measuring device.

  The bore measuring device disclosed in Japanese Patent Publication No. 2007-248303 is lowered into the cylinder after disassembling and removing the exhaust valve of the cylinder. The bore measuring device includes an elongated base body provided with two sets of at least three foldable holding arms configured to come into contact with the inner wall of the cylinder. A measurement arm having a measurement sensor is provided between the holding arms. The holding arm and the measuring arm are arranged in the operating position after the bore measuring device is lowered into the cylinder so as to measure the cylinder inner diameter while holding the bore measuring device in a predetermined position.

  Measuring the cylinder inner diameter of a small engine by inserting a measuring device through the mounting hole of the fuel injection device of the cylinder cover is based on published prior art such as Japanese Patent Publication No. 2003-1945506. Known. This measuring device is portable and is connected jointly with one arm that swings outward and contacts the inner wall of the cylinder. Since the insertion hole is inclined with respect to the center axis of the cylinder, it is possible to measure the cylinder inner diameter only in a limited area at the top of the cylinder.

  It is an object of the present invention to facilitate the measurement of cylinder liner wear while a two-stroke crosshead engine is temporarily inactive. It is also an object of the present invention to be able to perform such wear measurements very quickly, preferably very quickly so that the time required to perform cylinder liner wear measurements can be covered during standard port operations. Is to make it.

  For this reason, the method of the present invention is characterized by the following. The engine is a long stroke engine with a stroke to bore ratio of at least 2.4, the scavenging port is at the bottom of the cylinder liner, and the diameter measuring device is at least one other position along the length of the cylinder liner. Moving, the at least one other position is in the upper part of the cylinder liner, the diameter measuring device performs a measurement of the inner diameter of the cylinder liner at the at least one other position, and the diameter measuring device at each position, A diameter measurement is obtained as a first electronic parameter representing the diameter, and a corresponding height position of the diameter measuring device in the cylinder is determined.

  A two-stroke crosshead engine of the type related to the present invention is a uniflow scavenging engine, wherein each cylinder liner is provided with a circumferential row of scavenging ports at the bottom of the cylinder liner and the top end of the cylinder liner. A single exhaust valve is disposed in the center of the cylinder cover attached to the cylinder. At the end of the combustion stroke, when the piston moves down through the scavenging port and the exhaust valve opens, scavenging and intake air flows upward through the cylinder liner, sweeping the combustion gas out of the combustion chamber. This scavenging flows in one direction upward from the bottom of the cylinder liner during the scavenging process. The scavenging port has a fairly large opening area so that a sufficient flow of pressurized air flows into the cylinder liner when the exhaust valve is open.

  Inserting the diameter measuring device through the scavenging port into the cylinder liner allows the diameter measuring device to be placed inside the cylinder liner without disassembling the cylinder cover or the scavenging valve housing. Thereby, this insertion can be performed immediately after the engine has been turned off and the overall duration of the measurement process is greatly reduced. In addition, unlike the prior art method which requires dismantling of large cylinder parts, the engine cylinder is hardly affected by the measurement.

  The diameter measuring device acquires a measured value of the diameter as a first electronic parameter representing the diameter. This is because of this diameter for reading after removal of the diameter measuring device from the cylinder liner, or for quick movement to a receiver that transfers the measurement values to the memory of the device outside the cylinder liner. It enables the measuring device to store the measured values in a simple manner. Therefore, there is no need to visually observe the measurements, and many measurements inside the cylinder liner after placing the diameter measuring device on top of the cylinder liner for measurements typically where the wear is greatest. Can be executed.

  At the beginning of the combustion stroke, the pressure level in the combustion chamber is high when the piston is near the top of the cylinder liner, so the piston ring pressure against the inner surface of the cylinder liner is also high, and at the same time between the piston ring and the cylinder liner. Due to the relatively small relative movement of the cylinder, it becomes more difficult to maintain sufficient lubrication between the piston ring and the surface of the cylinder liner. Further, in combination with the high temperature of the upper portion of the cylinder liner, the most wear is caused in the upper portion. This engine is a long stroke engine and the ratio of stroke to bore (S / B) is at least 2.4, preferably greater than S / B = 3.0. During the measurement at the upper part of the cylinder liner, this diameter measuring device is arranged inside the cylinder liner at a position remote from the scavenging port.

  Preferably, a height measuring device is used to measure the position of the diameter measuring device inside the cylinder liner. This height measuring device acquires a distance measurement value as a second electronic parameter representing the distance. The use of a height measuring device in conjunction with a diameter measuring device allows for measurement of the diameter without any interface with the control device of the internal combustion engine. The height measuring device pays attention to the measurement of the height position inside the cylinder liner of the diameter measuring device when the diameter measuring device performs the diameter measurement. This allows diameter measurements to be associated in a simple manner with specific locations on the cylinder liner so that the wear curve of the liner can be drawn or calculated.

  In a further development of the method according to the invention, a plurality of sets of corresponding values of the first electronic parameter and the second electronic parameter are preferably recorded as stored values in the memory. Recording the corresponding values of the first and second electronic parameters allows for failsafe electronic handling of the data. And if this recording is performed when this diameter measuring device is placed inside the cylinder liner during the measurement process, it means that there is no need to communicate with the outside of the cylinder during the measurement process. The entire process is self-contained. The collected data set can be retrieved, for example, from memory after the measurement is complete and the device is removed from the cylinder liner.

  Height measurement can be performed in several different ways. One possibility is to have the height measuring device measure the height from the position of the diameter measuring device inside the cylinder liner to the lower surface of the exhaust valve. In this case, when the height measuring device is arranged on or integrated with the diameter measuring device, the combined device is such that the common operation to be performed at the scavenging port at the bottom of the cylinder liner only needs to be inserted inside the cylinder liner. To return to. Another possibility is to have the height measuring device measure the height (length in the vertical direction) to the position of the diameter measuring device inside the cylinder liner. In this latter case, the height measuring device must be mounted on the top of the cylinder. This can be achieved, for example, by installing a height measuring device in the access hole designed for this in the cylinder cover or in the mounting hole for the fuel injector after removal of the fuel injector. Yet another possibility is to place the height measuring device on a surface that is stationary relative to the engine frame and measure the height of the part of the piston that supports the diameter measuring device. It is possible to correct the measured height by the difference in height between the measuring part on the piston and the actual position of the diameter measuring device on the piston.

  When the height measuring device is attached to the cylinder cover, the height measuring device extends from the outside of the cylinder to the inside of the combustion chamber, so data is transferred from the inside of the cylinder to a device arranged outside the cylinder. It can be used during the measurement process as a means to do. One advantage of this is that despite the fact that the cylinder volume and the piston and cylinder cover enclosed inside the cylinder liner act as a Faraday box that makes electronic communication impossible, data communication And reading can be achieved. Therefore, a receiver for receiving a signal transmitted from a transmitter of the diameter measuring device is preferably provided in the height measuring device.

  A diameter measuring device that can travel on the inner surface of the cylinder liner and move the diameter measuring device upward along the inner surface of the cylinder liner, for example, with a lifting device that is an electrically driven wheel (wheel). It is possible to realize. Alternatively, the diameter measuring device may comprise a line fixed to the device extending upwards inside the cylinder and passing through a suitable opening in the cylinder cover. This line can be used to pull the diameter measuring device to the desired measurement position in the cylinder when in place. However, in another preferred method, the diameter measuring device is disposed on the piston and moved in the height direction of the cylinder liner by rotating the crankshaft of the engine. In this case, the piston crown is used as a platform for supporting the diameter measuring device during the measurement and for moving the diameter measuring device up and down inside the cylinder liner. A two-stroke crosshead engine typically has a rotating wheel connected to a crankshaft, possibly via a thrust shaft. The rotating wheel is engaged via a rotating gear with an electric motor that is activated to rotate the crankshaft when the engine is not in operation. Prior to placing the diameter measuring device on the piston, a flexible ring or circular plate can be inserted into the scavenging port and placed on the piston. This flexible ring or circular plate provides a clean surface on which the diameter measuring device can be supported. Using a flexible ring as a support member between the piston crown helps to perform small movements of the diameter measuring device that are not obstructed by coke deposits on the piston crown. If necessary, large coke deposits on the piston crown can be flattened or removed in the area supporting the diameter measuring device.

  As mentioned above, the method of the present invention involves the detection of the height position inside the cylinder liner by the use of a device designed for it. However, the piston in the cylinder height direction is based on the crankshaft rotation angle of the engine relative to the crankshaft rotation angle corresponding to the piston position at top dead center (TDC) or bottom dead center (BDC). It is also possible to obtain the position of. When the rotation angle of the crankshaft corresponding to the piston position at the bottom dead center or the top dead center is known for a specific cylinder, the arbitrary rotation angle of the crankshaft is related to the corresponding height position of the piston inside the cylinder liner. It is easy. Instead of using bottom dead center or top dead center as the reference point, it is also possible to use a position where the upper surface of the piston is horizontal with the upper edge or the lower edge of the scavenging port. These positions of the piston can be easily grasped when the diameter measuring device is inserted onto the upper surface of the piston crown through one of the scavenging ports.

  Alternatively, a thin string hanging from the diameter measuring device is connected to the diameter measuring device, and a marking is provided on the string that can be manually detected or read visually at the scavenging port during the measurement. The marked string can extend upward inside the cylinder and exit out of a suitable opening in the cylinder cover. In either case, the height position of the diameter measuring device can be manually noted during the measurement process.

  The present invention relates to a diameter measuring apparatus capable of measuring the inner diameter of a cylinder liner of a two-stroke crosshead engine. The diameter measuring device includes a frame structure having two protrusions extending on one side thereof, and an elongated measuring arm extending on the opposite side of the frame structure. The measuring arm is urged so as to be displaced away from the two protrusions, and is connected to a meter that measures the distance the measuring arm is displaced with respect to a predetermined design value of the inner diameter of the cylinder liner. Has been.

  In one embodiment of the diameter measuring device of the present invention, the measuring arm is accompanied by a drive that can retract the measuring arm to the retracted inoperative position. The drive is electronically controlled to displace the measurement arm in the inoperative position or to place the measurement arm in the extended position in which the bias in the direction away from the two protrusions is activated. And the said meter converts the position of the said measurement arm when it exists in an expansion | extension position into the 1st electronic parameter showing a diameter.

  The drive that retracts the measuring arm to the retracted non-actuated position is operated to insert the diameter measuring device through the scavenging port in a safe manner and to be correctly positioned in place above the piston. After placement of the device and upward movement through the area of the scavenging port, the drive device is electronically activated to displace the measuring arm to the extended working position. At this position, the biasing force of the measuring arm displaces the two protrusions so that they abut against the inner surface of the cylinder liner, and the diameter measuring device is correctly arranged, and preparation for measuring the inner diameter of the cylinder liner is completed. There is no need to visually read the meter because the meter converts the diameter to the first electronic parameter. In this way, the diameter of the cylinder liner is automatically read and stored in the device or transmitted to the receiver for later retrieval.

  In a preferred embodiment, the meter is calibrated to measure the diameter with an accuracy in the range of 0.1 to 0.005 mm when the inner diameter of the cylinder liner is in the range of 250 mm to 1100 mm. It is advantageous to be able to measure very small wear values, since cylinder wear typically progresses very slowly during long engine operation. For example, when measuring wear with an accuracy of 0.01 mm in spite of a cylinder liner diameter of 60, 80 or 90 cm, abnormal wear is detected at an early stage and, for example, a large amount of cylinder lubricant is supplied. It is possible to take corrective actions necessary for the operating state of the cylinder, such as cleaning the piston ring or treating the inner surface of the cylinder liner.

  In one embodiment of the present invention, by providing the diameter measuring device with the first temperature sensor that measures the temperature of the diameter measuring device, the accuracy of the measured diameter can be increased. This temperature measurement allows the measurement value to be corrected based on a change in length depending on the temperature in the measuring direction of the diameter measuring device. This is important when the arm material exhibits a large length change due to temperature changes.

  In other or further embodiments, the diameter measuring device comprises at least one second temperature sensor that measures the temperature of the inner surface of the cylinder liner. The advantage of this embodiment is that the diameter can be measured by inserting a diameter measuring device inside the cylinder liner immediately after the engine is stopped. Cylinder liner temperature measurement allows compensation for changes in measurement values caused by changes in the temperature of the cylinder liner material. In the measurement of the prior art, the cylinder cover has to be disassembled. However, due to the temperature of the cooling water (about 80 ° C.), it takes a considerable time until the temperature of the cylinder liner becomes more uniform. When measuring the temperature of the cylinder liner along with the measurement of the diameter, whether the temperature of the cylinder liner changes along its height is no longer important for the accuracy of the diameter measurement and therefore the diameter until the liner cools to a uniform temperature. There is no need to wait for the measurement. Preferably, at least one second temperature sensor is arranged on one or both of the two protrusions.

  In another embodiment of the present invention, a height measuring device is used to measure the relative height so that the height position of the diameter measuring device inside the cylinder liner can be measured substantially continuously. Use. The height measuring device is emitted from the laser light source, a mounting member for fixing the height measuring device to a mounting position of the mounting opening for the fuel injector of the cylinder cover, and a position at which the height measuring device is mounted. And a mirror that reflects the reflected light rays downward substantially parallel to the central axis of the cylinder liner. The height measuring device obtains a distance measurement value as a second electronic parameter representing the distance to the diameter measuring device disposed on the piston inside the cylinder liner. In another embodiment, the height measuring device comprises a laser light source disposed on the diameter measuring device and emitting a laser beam upward substantially parallel to the central axis of the cylinder liner, The measuring device obtains a distance measurement value as a second electronic parameter representing the distance to the lower surface of the exhaust valve. The height measurement device calculates distances, instead of laser light sources, such as radiation sources that emit microwaves or other frequencies, such as those used in radar or sonar, and receivers that detect reflected waves. And a processing device.

  The combination of measuring with a diameter measuring device and measuring with a laser source is at a larger number of dispersed locations than was possible with conventional measuring devices that provide manual measurements at very few dispersed pre-determined locations. Provides a more accurate measurement of cylinder liner diameter. In practice, this height measuring device makes it possible to obtain a continuous or nearly continuous measurement of the cylinder liner diameter along the inner surface which acts as the sliding surface of the piston ring on the cylinder liner.

  The invention also relates to a flexible ring for use in the method of the invention. The flexible ring is annular and, in an unfolded state, has an outer diameter that is less than the predetermined design value of the cylinder liner's predetermined inner diameter and greater than 30%, preferably at least 50% of the inner diameter design value. Having a large inner diameter.

  It was confirmed that by manufacturing the ring as an annular flexible ring, the ring could be easily inserted from the scavenging port and placed on the piston. This flexible ring is a 1-2 mm thick ring of suitable synthetic resin, such as silicon, PTFE, or PEHD or PDM, while providing a clean surface on which the diameter measuring device can be supported. , Typically manufactured from a soft and strong material. Materials that reflect the light from the laser light source are also suitable. This effect of the ring alleviates the problems that can occur when significant coke is deposited on the upper surface of the piston crown, because the surface on which the coke is deposited absorbs light from the laser source.

  Hereinafter, exemplary embodiments of the present invention will be described in more detail with reference to preferred embodiments shown in schematic diagrams.

The top view of the diameter measuring apparatus by this invention. The side view of the height measuring apparatus by this invention. Sectional drawing of a 2-stroke crosshead internal combustion engine. The figure which looked at the diameter measuring apparatus arrange | positioned inside a cylinder liner from upper direction. (A)-(d) is principal part sectional drawing shown with the diameter measuring apparatus introduced into the inner side of the cylinder liner, and the height measuring apparatus used in one Embodiment of this invention.

  FIG. 1 shows an embodiment of a diameter measuring device 10 that can measure the inner diameter of a cylinder liner of a two-stroke crosshead internal combustion engine. The diameter measuring device 10 includes a frame structure 11 having two protrusions 12 and a measurement arm 13, and the two protrusions 12 extend to one side of the frame structure 11, and the measurement arm 13 includes the frame structure 11. It extends to the opposite side and is biased by a spring. The two protrusions 12 are substantially spherical and serve as support points for the frame structure 11 on the surface of the piston crown and as contact points 17 for the inner surface of the cylinder liner.

  The measuring arm 13 is also provided with a spherical knob that serves as a contact point 17 that contacts the inner surface of the cylinder liner. All of the two protrusions 12 and the measurement arm 13 can be provided with metal balls for contacting the cylinder liner wall. The measuring arm 13 is urged so as to be displaced away from the two protrusions 12, and the electronic meter 14 measures the displacement distance of the measuring arm 13 with respect to the design value of the predetermined inner diameter of the cylinder liner. It is connected to the. The electronic meter 14 is a VIGGO A.1. It is of the KJAER type and is calibrated to measure the diameter with an accuracy in the range of 0.1 to 0.005 mm, typically 0.01 mm.

  The measurement arm 13 is controlled to be in an inoperative state or an operational measurement state by an actuator 20 that is controlled by the electronic circuit module 15 and supplied with electric power from the battery 16. In the illustrated embodiment, the actuator 20 is designed as an electric motor that rotates the spindle 21. The end region of the spindle 21 supports a male screw that passes through the opening of the bracket 40 and is screwed into the nut. The nut is fixed to the bracket 40 in the rotational direction, and when the spindle rotates, it is screwed inwardly or outwardly on the spindle. The leg portion of the bracket 40 is fixed to a bar 42 that is fixed to the end region of the measurement arm 13 and extends in the transverse direction (lateral direction). The positions of the nut, bracket 40 and bar 42 shown in FIG. 1 correspond to the position where the measuring arm 13 is fully extended. When the spindle rotates in one direction, the nut is displaced in the direction of the actuator 20 and pushes the bottom of the U-shaped bracket 40, so that the bar 42 and the measurement arm 13 are pulled together with the bar 42 and the measurement arm 13. It is done. This retracts the measuring arm, but the opposite is true when the spindle rotates in the other direction. The housing 41 is stationary with respect to the frame structure 11. The measurement arm 13 is attached to a bearing in the housing 41 and can slide in the longitudinal direction with respect to the housing 41. The compression spring is attached around the measurement arm 13, and its inner end abuts against the end wall of the housing 41 and its outer end abuts a spring guide fixed to the measurement arm 13. Therefore, this compression spring urges the measurement arm 13 in a direction that leaves the housing 41 and moves away from the spindle 21. The end of the measuring arm 13 protrudes through an opening in the end wall of the housing 41 and supports a bar 42 that is fixed to the end region of the measuring arm 13 and extends in the transverse direction. In a position where the measurement arm 13 is not actuated, the compression spring biases the measurement arm to a terminal position where the opposing surface on the outer side of the bar 42 contacts the opposing end surface on the inner side of the housing 41.

  When the actuator 20 displaces the measuring arm 13 outward and the abutment point 17 contacts the inner surface of the cylinder liner, the displacement of the measuring arm stops, but during the further outward displacement, the nut and the bottom of the U-shaped bracket 40 As a result, a measurement arm 13 is released and a diameter of the cylinder liner is accurately measured. The actuator / spindle mechanism is provided with a stopper member (not shown) that stops the current to the actuator when the nut reaches a predetermined outer end position.

  The electronic meter 14 has a measuring pin 43 that is biased to abut against the opposing surface inside the bar 42 extending in the transverse direction. Thereby, the electronic meter 14 records the displacement of the measuring arm 13 by measuring the current position of the bar 42 extending in the transverse direction. The bracket 49 fixes the position of the housing of the electronic meter 14 with respect to the bottom plate of the diameter measuring device 10. When the measurement of the diameter is completed and an activation signal is transmitted to the electronic circuit module 15, the actuator 20 is actuated to displace the housing 41 in the inward direction and come into contact with the bar 42 extending in the transverse direction. 13 is a non-actuated position. Then, since both the housing 41 and the measuring arm 13 are arranged at a distance from the inner surface of the cylinder liner, the diameter measuring device 10 can be operated and taken out from the cylinder liner, or the diameter of the cylinder liner can be operated. It can also be repositioned on the piston crown to measure other sets. This rearrangement allows measurement of the diameter in the transverse direction of the engine and in the longitudinal direction of the engine.

  The electronic meter 14 is connected to the electronic circuit module 15 via an RS232 connection and transfers the measured electronic parameters to the memory or communicates the measured electronic parameters to the receiving device 50 (see FIG. 2). It is supposed to be. Electric power is supplied to the electronic meter 14 and the electronic circuit module 15 from a battery 16 attached to the frame structure 11. This battery has a capacity of about 8 hours corresponding to one working day, for example. The electronic circuit module 15 has a full duplex transceiver unit, such as a standard Bluetooth 2.0 module, for communicating with the receiving device 50.

  Further, the diameter measuring device 10 includes a first temperature sensor disposed on the frame structure 11 to measure the temperature of the diameter measuring device 10. Since both the frame structure 11 and the measuring arm 13 are made of metal, when the measuring arm 13 is 80 cm long to measure the largest cylinder diameter, the ambient temperature affects their length. Can affect.

  In addition, the diameter measuring device 10 can include a second temperature sensor that measures the temperature of the inner surface of the cylinder liner. Preferably, at least one second temperature sensor is arranged on one or both of the two protrusions 12. However, in other embodiments, the second temperature sensor is disposed on the frame structure 11 between the two protrusions 12 and can be, for example, a spring blade temperature sensor.

  The height measuring device 50 shown in FIG. 2 comprises a cylindrical metal tube 53, which is placed next to the electronic circuit module 52 at one end, for example commercially available from Bosch. A laser light source 51 is provided. This laser light source irradiates a laser beam through a cylindrical metal tube 53 toward an opposite end having a concave portion 54 in the horizontal direction where a mirror 55 for reflecting the laser beam is provided. It is in a suitable position to do. At the free end of the cylindrical metal tube 53, an antenna 56 configured to transmit / receive signals to / from the diameter measuring device 10 is provided. Wireless communication is controlled by an electronic circuit module 52 that collects received measurements. The mounting jig 58 is fixed to and extends from the cylindrical metal tube 53, and holds the height measuring device 50 in a correct position during use. The metal tube 53 is also provided with a guide 57 that assists in changing the orientation of the device during insertion and attachment. As shown in FIGS. 5A to 5D, the height measuring device 50 is attached to the fuel injector mounting opening (fuel injector mounting hole) in the cylinder cover. ing. The actual angle between the longitudinal direction and the vertical direction of the metal tube is determined by the direction of the mounting opening, but the angular range is typically 10 to 20 degrees.

  With the height measuring device 50 attached, the mirror 55 causes the light emitted from the laser light source 51 to be offset in the radial direction with respect to the cylinder liner in a direction substantially parallel to the central axis of the cylinder liner 106. Reflected downward. Since the irradiated light is reflected from the surface of the piston 102 or the surface of the diameter measuring device 10, the height measuring device 50 has a downward distance to the diameter measuring device 10 disposed on the piston 102 inside the liner liner 106. A measured value is acquired (FIG. 5A).

  The actual measured distance is calibrated by measuring the height of the piston 102 at a well-defined position, eg, bottom dead center. This calibration can be used to compensate for the thickness of the coke deposit and the annular ring on which the diameter measuring device 10 is located. This calibration or compensation can be done by an external computer connected to the electronics module 52, either wirelessly or by cable connection, or manually calculated based on values obtained and stored during the measurement process. You can also.

直径測定装置は、高さを３０ｍｍ以下とし、かつ幅を１００ｍｍ以下とすることにより、様々な寸法の掃気ポートの全てを介して挿入することができる。当然、直径測定装置は他の寸法、および直径測定装置の個々のモデルが実際のエンジンのポート寸法に適合するように様々な寸法に製造できる。 FIG. 3 shows a two-stroke crosshead internal combustion engine 100, which is, for example, a type ME or type MC two-stroke engine manufactured by MAN Diesel SE or a type RTA or RT-flex manufactured by Wartsila. . The engine includes a plurality of cylinders, for example, 4 to 14 cylinders, but in each cylinder 101, the piston 102 can move between the top dead center TDC and the bottom dead center BDC. At the bottom dead center, the upper part (upper surface, upper end) of the piston is directly below the circumferential row of the scavenging ports 103 arranged in the lower part of the cylinder liner 106 inside the cylinder 101. The inner diameter of the cylinder is in the range of 250-1100 mm, but this diameter measuring device is different from measuring a large diameter cylinder, such as smaller diameter cylinders, eg 250 mm-350 mm, 250 mm-400 mm, 250 mm-420 mm. , 250 mm to 460 mm, 250 mm to 500 mm and 250 mm to 600 mm in the range of one or more diameter cylinders. Typical dimensions for individual scavenging ports are given in Table 1 below.

The diameter measuring device can be inserted through all the scavenging ports of various dimensions by setting the height to 30 mm or less and the width to 100 mm or less. Of course, the diameter measuring device can be manufactured in other dimensions and various dimensions so that the individual models of the diameter measuring device fit the actual engine port dimensions.

  In FIG. 3, the piston 102 is in the vicinity of the top dead center. A cylinder cover 105 closes the cylinder at the upper end of the cylinder liner 106. An exhaust valve 104 is attached to the housing at the center position of the cylinder. When the exhaust valve 104 is in an open position during operation, the exhaust gas from the combustion chamber flows to the exhaust gas receiver 120 through the exhaust gas passage. The loaded air receiver 122 supplies compressed air to a chamber 123 surrounding the scavenging port 103 of the cylinder 101. Exhaust gas flows through the compressor portion of the turbocharger 121 that supplies compressed intake air and scavenging to the loaded air receiver 122.

  When the engine is stopped and deactivated, the crankshaft of the engine can be rotated by the electric motor 115. The electric motor 115 is typically engaged with a rotating device 117 that is attached to a thrust shaft of the engine and connected to a crankshaft via a turning device 116. As the engine crankshaft rotates slowly by the motor 115, the piston moves up or down inside the cylinder liner. This rotational movement can be controlled manually, for example by pressing an activation button, or it can be programmed into a stored procedure suitable for performing diameter measurements in connection with the present invention. During this rotational movement, the exhaust valve is preferably held in an open position.

When the engine is stopped and deactivated, the side door of the cylinder portion associated with the cylinder to be measured is opened to allow access to the space surrounding the lower portion of the cylinder liner. The engine is rotated by the turning gear until the upper surface of the piston is at a position below the row of scavenging ports, that is, until the piston is at the bottom dead center as shown in FIG. The side door is disposed adjacent to the scavenging port 103.
Next, the diameter measuring device 10 is operated to be inserted through one of the scavenging ports 103 while setting the direction of the bottom surface thereof in the vertical direction, and when entering the inside of the cylinder liner 106, this device is rotated. 4 and as shown in FIG. 5A, it is disposed on the upper portion (upper surface, upper end) of the piston 102.

  If desired, an annular ring 130 is inserted through the scavenging port and placed over the piston 102 before inserting the diameter measuring device 10. The ring is flexible so that it can be folded during insertion. When the ring is deployed, the ring fits over the cylinder crown. This is because the outer diameter is smaller than the inner diameter of the cylinder liner. In one embodiment, the ring may be a circular thin plate of material that covers the entire piston. However, the ring preferably has an inner diameter that is greater than 50% of the aforementioned design value of inner diameter to facilitate its introduction and placement. This is because the amount of material of the ring is reduced. The ring is made of a suitable flexible material, such as PTFE or synthetic resin. Optionally, before placing the ring or diameter measuring device on the top (top, top, top) of the piston, the coke deposits in the area supporting the diameter measuring device 10 on the piston may be flattened or removed. it can.

  In FIG. 5A, the diameter measuring device 10 is disposed on the piston 102. The diameter measuring device 10 is disposed on the piston 102 with its two protrusions 12 approaching the outer peripheral edge of the piston 102. When the insertion of the ring and / or diameter measuring device 10 is completed, the crankshaft of the engine is rotated. Then, as shown in FIG. 5B, the piston moves upward to a position where the upper surface of the piston is near the upper end of the scavenging port.

  Then, when the actuator 20 places the measurement arm 13 in the operating position, the biasing force on the measurement arm causes the two protrusions 12 to abut one of the inner surfaces of the cylinder liner. Then, when the transversely extending bar 42 is released from contact with the housing 41, the meter 14 operates to detect and measure the actual diameter of the cylinder liner. The activation of the actuator 20 can be performed by a time delay device that performs the activation after the diameter measuring device 10 is arranged at a predetermined position on the upper part of the piston and after a preset period, for example, after 3 minutes, This allows rotation of the crankshaft. Alternatively, the activation of the actuator can be caused by a control signal transmitted to the electronic circuit module 15. This control signal can be transmitted via the transmitter when the height measuring device is used.

  After activation, the diameter measuring device 10 performs an inner diameter measurement inside the cylinder liner. When the engine is rotated during the measurement, the piston 102 moves toward the top dead center together with the diameter measuring device 10 as shown in FIG. The diameter measuring device 10 measures the diameter D of the cylinder liner as an electronic parameter representing the diameter of the cylinder liner. When the piston is at top dead center, if the space above the piston in the combustion chamber is insufficient to accommodate the diameter measuring device, the piston stops rotating before reaching this position.

  After the measurement is completed, the crankshaft is rotated so that the piston moves downward in the cylinder. The middle position is shown in FIG. The diameter measurement can also be performed while the piston moves downwards, and the double measurement result allows inspection of the measured data. Measurements can be performed at short intervals, for example, twice per second. This allows the measurement of a nearly continuous diameter of the cylinder. This is because the piston moves slowly.

  It is desirable to measure the diameter of the cylinder liner along the length of the cylinder in both the transverse (transverse) and longitudinal (longitudinal) directions for the vessel. One way to perform measurements along the length of the cylinder liner, both laterally (transversely) and longitudinally (longitudinal) with respect to the ship, is to place the piston in the position shown in FIG. 5 (a). When reaching again, the diameter measuring device 10 is manually moved to another position. Manual movement includes rotating about 90 degrees about the longitudinal axis of the device cylinder liner. Therefore, during the first measurement cycle, the diameter measuring device 10 is arranged on the piston 102 along the longitudinal direction (longitudinal direction) of the ship, for example. During the second measurement cycle, the diameter measuring device 10 is arranged along the horizontal direction (transverse direction) of the ship. Alternatively, the diameter measuring device 10 can be moved between two positions by wheels and actuators mounted on the diameter measuring device 10. For example, by moving the piston when it reaches the top dead center, two cycles during one cycle of rotating the engine corresponding to the movement of the piston 102 from the starting position to the top dead center and back to the starting position again. A complete measurement of the cylinder liner diameter in the direction can be performed.

  When the height measuring device 50 is used, the height measuring device 50 can automatically detect when the piston 102 reaches the position shown in FIG. The height measuring device 50 can automatically send a signal for operating the diameter measuring device to start the measurement. When the receiver of the electronic circuit module 15 receives the signal, the measuring arm 13 is placed in the operating position for measurement. While the engine is rotating, the inner diameter of the cylinder liner is measured by a diameter measuring device, and the first electronic parameter is stored in a memory within the device or transmitted to a height measuring device. The height measuring device transfers the received first electronic parameter together with the corresponding second electronic parameter to the computer.

  While measuring the diameter, the height measuring device measures the height. That is, the measured value of the position and height of the piston and the measured value received from the diameter measuring device 10 are stored in the electronic circuit module or transmitted to the external computer as described above. In a preferred embodiment, the measured value of the diameter measuring device 10 is transferred to the height measuring device 50. Temperature measurements can also be stored or transmitted simultaneously. Thus, while measuring the cylinder, the cylinder liner diameter and corresponding height measurements are combined and stored in the electronics module 52 for later use, or the cylinder liner diameter and corresponding height measurements. The measurement parameters are sent directly by the electronic circuit module 52 to the external computer.

  One possible embodiment is to attach a camera or photographic device to the diameter measuring device to take a picture of the inner surface. This photograph can be used to evaluate the condition of the working surface, i.e. the inner surface of the cylinder liner, on which the piston ring on the piston slides. Therefore, an early warning of excessive wear can be detected, for example, by observing discoloration of the inner surface of the cylinder liner.

  In other embodiments, the diameter measuring device may comprise a device for measuring distance based on measurement with a laser beam. It is well known to use an apparatus that emits laser light for distance measurement. This laser device can be mounted on a frame supported at three or more locations like the diameter measuring device described above. This laser distance measuring device can irradiate the laser beam in two directions opposite to each other, so that it only needs to be placed on the piston at a distance from the inner surface of the cylinder liner in order to perform the measurement. . The laser device can be mounted on a vertical shaft extending from the central position of the housing of the device so that it can emit a laser beam mainly in the horizontal direction when placed on the piston crown. With such positioning on the piston crown of the laser device, an electric drive motor can be used to rotate the laser device when performing measurements. In this way, the inner diameter of the cylinder liner can be detected continuously over substantially the entire inner surface. This is because when the piston moves upward inside the cylinder liner, the laser beam scans the inner surface of the cylinder liner with a spiral movement. The measured first electronic parameter can be stored in a memory or transmitted to a receiver, for example a receiver on one height measuring device of the type described above.

  In both the diameter measuring device 10 including the laser device and the diameter measuring device including the measuring arm 13 of the type described above, the position of the piston in the height direction of the cylinder liner 106 is acquired based on the value of the rotational position of the crankshaft. Can do. As described above, there is a clear correlation between the position of the piston inside the cylinder and the rotation angle of the crankshaft. Based on this relationship, the height position of the piston can be calculated from the rotation angle (reference value) corresponding to the bottom dead center position of the piston and the actual rotation angle information of the crankshaft when the diameter measurement is performed. it can.

  The height can be measured by other methods. When the diameter measuring device 10 is arranged on the piston 102 and moves up and down inside the cylinder liner by the movement of the piston 102, the height position of the diameter measuring device can be determined based on the height position of the piston. The height position of the piston can be measured by using the intermediate bottom 141 in the engine frame as a support surface of the distance measuring device 140 (see FIG. 3). This distance measuring device can visually recognize a part of the piston such as a lower part of the piston skirt or a part where a lower surface of a piston ring attached to a piston ring groove (not shown) on the piston is exposed. Thus, it is arranged below the piston 102. This distance measuring device can be based on distance measurement with a laser. The distance measured with this device can be corrected by the distance between a part of the piston and the position of the diameter measuring device in order to obtain the actual position of the diameter measuring device.

  The various embodiments described above can be combined with other embodiments. Also, specific features may be designed in other ways within the scope of the claims. In one embodiment, a height measuring device is placed in a region below the crosshead inside the engine to measure the position of the crosshead or crosshead shoe in the height direction, and then this distance measurement is calculated to calculate the cylinder liner. It can be converted into the height position of the piston in the inside.

Claims (15)

A long stroke engine having a ratio (S / B) of stroke (S) to bore (B) of at least 2.4 and a scavenging port (103) is a two-stroke crosshead internal combustion engine (100 ) Is in a non-actuated state, the diameter measuring device (10) is introduced into the cylinder liner through the scavenging port (103) of the cylinder liner (106), and the measuring position for measuring the inner diameter of the cylinder liner is measured. A diameter measuring device (10) is arranged on the surface to measure the diameter of the cylinder liner of the engine,
Moving said diameter measuring device (10) along the longitudinal direction of the cylinder liner to at least one other measuring position in the upper part of the cylinder liner (106);
The diameter measuring device (10) measures the inner diameter of the cylinder liner at the at least one other measuring position;
The diameter measuring device (10) obtains a measured value of the diameter as a first electronic parameter representing the diameter at each measuring position, and the corresponding height position of the diameter measuring device (10) in a cylinder is A method characterized by being identified. Using a height measuring device (50) to measure the position of the diameter measuring device (10) inside the cylinder liner (106);
The height measuring device (50) acquires a distance measurement value as a second electronic parameter representing the distance.
The method according to claim 1, wherein: A plurality of sets of the first electronic parameters and the second electronic parameters are preferably recorded as stored values in a memory;
The method of claim 2 wherein: The height measuring device (50) measures the height from the position of the diameter measuring device (10) inside the cylinder liner to the lower surface of the exhaust valve (104).
The method according to claim 2 or 3, characterized in that: The height measuring device (50) measures the height to the position of the diameter measuring device (10) inside the cylinder liner (106).
The method according to claim 2 or 3, characterized in that: The fuel injection device on the cylinder cover (105) of the cylinder is removed, and the height measuring device (50) is introduced into the cylinder through the mounting hole of the fuel injection device,
Preferably, the height measuring device (50) includes a receiver for receiving a signal transmitted from a transmitter of the diameter measuring device (10).
6. The method of claim 5, wherein: The diameter measuring device (10) is arranged at the upper part of the piston (102) and moved in the height direction of the cylinder liner (106) by rotating the crankshaft of the engine,
Preferably, the flexible ring (130) is placed on the piston before placing the diameter measuring device (10).
A method according to any one of claims 1 to 6, characterized in that Rotation of the engine crankshaft in relation to the position of the piston in the height direction of the cylinder in relation to the rotation angle of the crankshaft corresponding to the position of the piston at either top dead center (TDC) or bottom dead center (BDC) Get based on angle,
The method according to claim 7, wherein: A diameter measuring device capable of measuring an inner diameter of a cylinder liner of a two-stroke crosshead internal combustion engine (100),
Comprising a frame structure (11) having two protrusions (12) and an elongated measuring arm (13);
The two protrusions (12) extend to one side of the frame structure (11) and the elongated measuring arm (13) extends to the opposite side of the frame structure (11);
The measuring arm (13) is biased to move away from the two protrusions (12), and is associated with a predetermined design value of the inner diameter of the cylinder liner. Connected to a meter (14) for measuring the displacement distance of the measuring arm (13),
The measurement arm (13) is associated with a drive (20) that can retract the measurement arm (13) to a lowered inoperative position;
The drive device (20) displaces the measurement arm (13) to a non-operating position or places the measurement arm (13) in an extended position where a biasing force acting in a direction away from the two protrusions (12) acts. Is electrically controlled to place,
The meter (14) converts the position of the measurement arm (13) when the measurement arm (13) is in the extended position into a first electronic parameter representing a diameter.
A diameter measuring device characterized by that.   The meter (14) is calibrated to measure the diameter with an accuracy in the range of 0.1 to 0.005 mm when the inner diameter of the cylinder liner (106) is in the range of 250 mm to 1100 mm. The diameter measuring device according to claim 9. The diameter measuring device (10) includes a first temperature sensor that measures the temperature of the diameter measuring device.
The diameter measuring device according to claim 9 or 10, characterized in that The diameter measuring device (10) comprises at least one second temperature sensor for measuring the temperature of the inner surface of the cylinder liner (106);
Preferably, the at least one second temperature sensor is located on one or both of the two protrusions (12),
The diameter measuring device according to any one of claims 9 to 11, wherein A distance measurement is obtained by the height measuring device (50) as a second electronic parameter representing the downward distance to the diameter measuring device (10) located on the piston in the cylinder liner (106). ,
The height measuring device (50)
A laser light source (51);
An attachment member (58) for attaching the height measuring device to the attachment position of the attachment hole for the fuel injection device of the cylinder cover;
A mirror (55) that reflects light emitted downward from the laser light source (51) in a direction substantially parallel to the central axis of the cylinder liner (106) when the height measuring device is in the mounting position. And have
The diameter measuring device according to any one of claims 9 to 12, A height measuring device (50) having a laser light source (51) for irradiating laser light upward in a direction substantially parallel to the central axis of the cylinder liner (106) is disposed on the diameter measuring device (10). And
The height measurement device (50) obtains a distance measurement value as a second electronic parameter representing an upward distance to the lower surface of the exhaust valve.
The diameter measuring device according to any one of claims 9 to 13, A flexible ring used with the diameter measuring device according to claim 9,
The flexible ring (130) is annular;
In the expanded state, an outer diameter smaller than the design value of the predetermined inner diameter of the cylinder liner,
An inner diameter greater than 30% of the design value of the inner diameter, preferably at least 50% of the design value of the inner diameter,
A flexible ring characterized by the above.

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